1. CoinMarketCap: CoinMarketCap is one of the most popular cryptocurrency apps in Sydney, Australia. It provides real-time market data, price charts, and news for over 2,000 cryptocurrencies. Users can track their favorite coins, set price alerts, and stay informed about the latest developments in the crypto market.

2. Binance: Binance is a leading cryptocurrency exchange platform that also offers a mobile app for trading on the go. Users can buy, sell, and trade a wide range of cryptocurrencies, as well as access advanced trading tools and features. The app is known for its user-friendly interface and high level of security.

3. Coinbase: Coinbase is a popular cryptocurrency wallet and exchange platform that allows users to buy, sell, and store a variety of digital assets. The Coinbase app offers a simple and intuitive interface, making it easy for beginners to get started in the world of cryptocurrency trading. Users can also set up recurring buys, track their portfolio, and securely store their coins.

4. Crypto.com: Crypto.com is a comprehensive cryptocurrency app that offers a range of services, including trading, staking, and earning interest on crypto holdings. Users can buy and sell over 100 cryptocurrencies, as well as access a Visa card that allows them to spend their digital assets in the real world. The app also features a built-in wallet and secure storage options.

5. Blockfolio: Blockfolio is a popular cryptocurrency portfolio tracker that allows users to monitor the performance of their investments in real-time. Users can track the prices of over 10,000 coins and tokens, as well as set up price alerts and view detailed charts and market data. The app is known for its user-friendly interface and customizable portfolio tracking features.